Preparation to discovery involves two more important yogas, Raja yoga and jnana yoga. Raja yoga and jnana yoga are usually practiced by people who have the tendency to meditate and realize the Truth. Raja yoga involves both physical and mental practice; Jnana yoga is reaching the higher stages of meditation by sheer knowledge.
The realization of the divinity through the control of the mind is called Raja yoga. Along with strong desire for realization, and mental purity, certain asanas (body postures) and modes of breathing are practiced to help concentrate the mind for realizing the Truth. The mind is gradually brought under control by Raja yoga. There are eight steps involved in Raja yoga.
Yama involves practice of non- injury to any beings mentally or physically, truthfulness, non-stealing, non-reception of gifts etc and it leads to mental purity, which is the preliminary step needed for the discovery of the Truth.
Physical cleanliness, contentment, austerity, study of scriptures and self surrender to God are involved in niyama. The first two steps are very important to continue with the rest.
3. Asana (body postures)
Body posture should be straight while meditating because while concentrating the nerve currents goes through new channels of the spinal column and so the spine should be erect.
4. Pranayama (control of vital energy)
Through breath one controls the prana, which is the universal energy which also exists in an individual. The most obvious manifestation of prana is breath. By pranayama, one controls the subtle forces of the body, the nerve currents. The mind is set in motion by these nerve currents. Therefore by pranayama, one controls the body as well as the mind. Akasa is the manifestation of prana. The entire gross forms manifest out of akasa, exists in akasa and resolve back to akasa. Thought is the highest expression of prana. All the mental and physical energies and physical forces like motion, electricity, magnetism etc are the expressions of prana. The biological functions in the body, functions of the nerve currents, operation of the mind are due to prana. The knowledge and control of this prana is pranayama.
Pranayama is the control of the prana in oneself. Controlling breath brings the prana in oneself to the vibration that is helpful in attaining to higher insight and understanding. It is the prana which controls the movement of the lungs. By pranayama, we access the prana in our body and bring it to the subtle vibration level, by which the mind become subtle and everything comes to knowledge.
The whole universe is a mass of matter with different states of vibration of the prana. Matter with higher vibrating frequency are divine objects like moon, sun etc and the matter with lower vibrating frequency become human beings, matter with still lower frequencies become plants, minerals and so on. The very subtle vibration of prana is called mind. If one gets into that subtle vibration through the regulation of prana within oneself, then the whole universe is seen as composed of subtle vibrations of thought. Each vibrating frequency level in akasa is a sphere, which has its own beings. By pranayama or by any other method, if we are able to attune the vibrations to our mind to that vibration, then we become aware of those spheres.
5. Pratyahara (restraint of the mind)
Perception takes place when the external instrument of perception (like eyes, ears and so on) convey impression to the brain and the mind reacts to the message. Thus the external instruments, the brain, and mind are required to have perception. Keeping the mind restraint from taking the path of perception is called pratyahara. By this, the mind concentrates more on the inner power and detaches from the sense objects.
Dharana is fixing the mind on a theme or object (external or imagination). Sometimes imagination will also help the mind to concentrate. Dharana reduces nervous excitement and calms the mind, and helps meditation. By dharana one can realize the objects of subtler planes.
Dhyana is taking the mind above the conscious level. Feeling of ego is present only when the mind is in the middle plane. There will be no sense of ego in the higher or lower planes. In this stage one experiences the unity of the universe. When the mind concentrates on a certain external or internal point, the mind flows as an unbroken point towards that point. This is dhyana.
8. Samadhi (meditation)
When dhayana intensifies it leads to samadhi or meditation. The highly concentrated mind engages in internal perception. The mind enters the super conscious state and many spiritual truths are revealed at this stage. Dharana, dhyana and samadhi are together called samyama. The final stage is similar to the final stage attained through various other methods.
Raja yoga is suitable for people who are interested in using their energy body. Yogis practice Raja yoga.
Janana yoga is the realization of man’s divinity through knowledge. Each form represents a point of consciousness in the infinite ocean of consciousness. The point of consciousness expresses itself through the body. An individual is only aware of his own point of consciousness, though he is capable of being aware of the infinite ocean of consciousness. He has to come out of his own point of consciousness and expand himself to realize this infinite Truth. Knowledge of the scriptures gives him guidance to attain this stage. Each soul is limitless, but one is not aware of this truth. Birth and Death are only assembling of the matter (finer or gross) around this point of consciousness. Atman is distinct from the body, mind and intellect. Clear understanding of this concept helps one to establish in this truth. Deep contemplation of this fact through nididhyasana helps the mind to merge in that very consciousness itself. There is only non-dual consciousness; it is the mind which makes it appear as many. When unity is perceived, diversity is not perceived. When diversity is perceived, unity is not perceived. Knowledge is inherent in man. External sources are only stimulations that help the knowledge to manifest.
An individual assumes that he is the mind, intellect and body. Mind and intellect are only impressions (vasanas) of our experiences, ideas and imaginations. Body is the outcome of the vasanas. A being is more precious than the vasanas and ideas. He is the Reality. Through jnana yoga one attains the knowledge that his Self is the Reality. He is bereft of the experiences. He is different from anatma. He is the Self, Atman. He is Brahman and all the rest are anatma.
These four yogas namely Karma yoga, Bhakti yoga, Raja yoga and Jnana yoga are the different methods which prepare a person to discover his Reality. Just like a pole or a stick which is used in a pole vault game to cross the bar, the yogas, scriptures, meditation and so on are just a pole to cross the bar of attachment and realize the Truth. An individual can choose a single yoga or combine two or more yogas together, as advised by his Guru. Whatever method one follows, the destination is the same that is the realization of the underlying unity of the Self, God, man and the world.
(also vide PREPARATION TO DISCOVERY- PART I)
The complete works of Swami Vivekananda, Vol V, Advaita Asrama, Kolkata
The four yogas of Swami Vivekananda (condensed and retold), Swami Tapasyananda, Advaita Asrama, Kolkata